为构建鸡法氏囊组织互补DNA(cDNA)文库,从3周龄鸡法氏囊组织提取总RNA,用偶联oligo(dT)磁珠纯化mRNA,用SMART(Switching methanism at 5′end of RNA transcrip)技术合成cDNA第1链,用LD-PCR方法扩增双链cDNA。经SfiⅠ酶切消化后,用CHROMA SPIN-400柱去除400 bp以下小片段,获得的双链cDNA与同样酶切的pMyr表达载体连接,电转化大肠杆菌获得cDNA文库。初始文库容量为2.8×10~6cfu,重组子比例为100%,插入片段的大小平均为1.2 kb。扩增后文库容量为8×10^(11)cfu·mL^(-1)。所建文库为鸡传染性法氏囊病毒受体基因克隆及功能研究奠定基础。
To compare the helper activities of different avian viruses for propagation of recombinant avian adeno-associated virus (rAAAV), AAV-293 cells were cotransfected with the AAAV vector pAITR-GFP containing green fluorescent protein (GFP) gene, the AAAV helper vector pcDNA-ARC expressing the rep and cap genes, and the adenovirus helper vector pHelper expressing Ad5 E2A, E4, and VA-RNA genes. Chicken embryonic fibroblast (CEF) or chicken embryonic liver (CEL) cells were cotransfected with the AAAV vector and the AAAV helper vector, followed by infection with Marek's disease virus (MDV), avian adenovirus, chicken embryo lethal orphan (CELO) virus or infectious bursal disease virus (IBDV). Infectious rAAAV particles generated by the two strategies were harvested and titrated on CEF and CEL cells. A significantly higher viral titer was obtained with the helper activity provided by the pHelper vector than by MDV or CELO virus. Further experiments showed that rAAAV-mediated green fluorescent protein (gfp) expression was overtly enhanced by MDV or CELO virus super infection or treatment with sodium butyric acid, but not by IBDV super infection. These data demonstrated that MDV and CELO viruses could provide weak helper activity for propagation of rAAAV, and rAAAV- mediated transgene expression could be enhanced by super infection with the helper viruses.
WANG An-ping SUN Huai-chang WANG Jian-ye WANG Yong-juan YUAN Wei-feng